CoinDesk adds that "At least one customer attempted to resell their bitcoin, but the large amount of the cryptocurrency offered soon drew attention even outside the exchange. The firm later cancelled the transactions and corrected the users' balances. However, a source suggests that the correction is still being agreed with one of the seven users who attempted to transfer the free bitcoin away from the Zaif platform."

The article didn't make this any clearer either, I thought one of the basic principles of bitcoin was that transactions can't be reversed? Did they not immediately transfer to a wallet they controlled? Or did their cash balance go negative and the company is going to ask for/sue for the balance? Anyone know more about this?

The article didn't make this any clearer either, I thought one of the basic principles of bitcoin was that transactions can't be reversed?

On the blockchain yes. But transactions take a long time to actually get verified in the blockchain which is why on these exchanges when you make a transaction to another customer in the exchange they may not even update it in the blockchain on the same day. It is all just written in Zaif's own ledgers, which they control much like any other bank doing internal accounting.

Hence also they are having problems with a customer who tried to move the bitcoin out of wallets controlled by Zaif.

It wasn't a Bitcoin transaction. It's basically a Bitcoin bank/exchange. A bunch of people deposit, they have an account with the exchange that has a certain balance, they can exchange with other users on the exchange and then withdraw.

I thought one of the basic principles of bitcoin was that transactions can't be reversed?

I doubt it really ever took place in the actual bitcoin block chain since the article states they bought bitcoin worth 20 trillion... many times more than the current market cap of bitcoin, making it impossible. It's would be confined to their order system since it was reversible.

The bug allowed the hacker to buy bitcoins at zero, so he typed in the number he wanted and was suddenly showing his number in the account without any actual trade happening... the exchange then killed all nonsense trades... and nobody was willing to take his bitcoins elsewhere. It's a market malfunction that CNBC/FBN/Bloomberg can have fun with, claiming that bitcoin still isn't safe yet.

This is exactly why stock trades (usually) take 72 hours to clear and settle, so that if there is electronic fuckery going on (unless it's sanctioned electronic fuckery like HFT), it can be rolled back and everyone gets a do-over.

You realize virtually no 'normal' people trade on the actual exchange, right? E-trade, etc. are all dark pools and they settle the majority of their trades internally so they never hit the actual open market.

HFT can be rolled back as well.

As to GP - yes, you can roll back a transaction with an opposite one following it. However, whether or not you can do that depends on having access to the wallet private key you need to send from. If someone bought BTC for $0.00 and sent that to a wallet the exchange di

There isn't even $20 trillion dollars worth of bitcoin in existence. You obviously wont be able to withdraw that to a real wallet. The bitcoin figure displayed on the website couldn't be backed by $20 trillion in real bitcoins.The exchange seems to have been screwed over by one customer withdrawing some of the bitcoin of the exchange, obviously not $20 trillion. But it seems some amount of real bitcoin was withdrawn.

Banks have to keep actual bills in a vault, and anything that moves bank-to-bank sends a truck rolling at 3am the next business day. Only Bank of America has problems finding everyone's money in the vaults.

Nope, that way it's easier to pull money straight from the aether. It's a simple extension of quantum uncertainty - if you look you could collapse the monetary function such that there is no money at all in there and go bankrupt. Whereas dollars that are snug and comfy and love each other very much in the dark can do something very special - and behold you have created more money!

Banks have to keep actual bills in a vault, and anything that moves bank-to-bank sends a truck rolling at 3am the next business day. Only Bank of America has problems finding everyone's money in the vaults.

You're reading some out of date encyclopedias. Banks keep digital ledgers these days and most certainly do not roll trucks at 3AM to cover transactions (how exactly would international money transfers work for that?)

Just like when people do trades in oil, bullion, etc. No one actually ships you a barrel (or a million) of oil. You 'own' whatever amount that happily sits (or will sit for futures) in the same storage facility it did when the last 5 people 'owned' it... all mixed together with what other pe

No, banks do not have to have actual bills in a vault. At the moment there are about $1.61 trillion dollars [federalreserve.gov] in circulation - that's all the notes and coins. It's only a fraction of the total US money supply [wikipedia.org].

you have an opportunity to steal an unlimited amount quickly.... and you choose 20 trillion dollars. He made the leap to being a thief, FFS use half a brain cell and try something you can get away with like a few million then transfer immediately. he may have had a chance to get away with that. Just a complete moron.

Bitvoins aren't software, they're blobs of data that check out under a specific formula. You can make a bitcoin out of thin air by computing a data blob that hasn't been used yet... but finding one takes more power usage than the bitcoin is worth.